解题方法
1 . 如图,已知三棱柱
,
平面
.D,E分别是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/22/03e0cf8e-497b-4d52-a9f4-08f68e020eed.png?resizew=177)
(1)证明:
平面
;
(2)设
与平面
所成角的大小是
,若
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d1d2e0f281222a5f289ea4008370aed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1cc117eb1a2d0ea7123b2ca898547546.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/310e5cf87aa443ca7f0ff80aba6dddc4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/22/03e0cf8e-497b-4d52-a9f4-08f68e020eed.png?resizew=177)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/063510e3c1fb6a7ccc3b8e3e3c7d660e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a8670759c61d785b9a336885df700b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb2cf0e95fdf1fd8a5b01d3dfd905e08.png)
您最近一年使用:0次
2 . 如图,设
为正方形
所在平面外一点,点
分别在
上,且
.证明:直线
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6670479a0083dd2dfd5ad55b47b1ab6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b60ed701b319dbdf1541a17e8da003f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/784bf07e745ca00fc0f8e8f4c0343b77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83ce5b706ae738b30640c0d44174a739.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/16/a68b3c38-9043-4a12-82e1-053c850503e1.png?resizew=144)
您最近一年使用:0次
2018-12-28更新
|
199次组卷
|
6卷引用:数学奥林匹克高中训练题(150)
3 . 如图所示的几何体中,
垂直于梯形
所在的平面,
为
的中点,
,四边形
为矩形,线段
交
于点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/8/09dbbc8d-1c79-4897-8778-2921326c7869.png?resizew=170)
(1)求证:
平面
;
(2)求二面角
的正弦值;
(3)在线段
上是否存在一点
,使得
与平面
所成角的大小为
?若存在,求出
的长;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c54c11863ae31dc12d880c44f823b32.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cc5addb203f4b6985880c4cef3ddc14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a5bf51c07144386bd23a422d9ceb140.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/8/09dbbc8d-1c79-4897-8778-2921326c7869.png?resizew=170)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c233b95865198572282d7a66ce689e94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134ef0b1a2669a09f05bd4dc2496f706.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b33b7213d99a817bff19bcf740a0697c.png)
(3)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb6ede9761b5b90f8dc137708e1ee90f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1b489c25405ce48699d4f0a62820bed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/037fb348109dc2063a268b10eb925a57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632917e61f4208959686d118c7f19231.png)
您最近一年使用:0次
2019-06-05更新
|
4463次组卷
|
11卷引用:2015年全国高中数学联赛黑龙江赛区预赛试题
2015年全国高中数学联赛黑龙江赛区预赛试题2015届北京市昌平区高三上学期期末质量抽测理科数学试卷天津市新华中学2019届高三高考模拟数学(理)试题(已下线)数学-2020年高考数学押题预测卷03(江苏卷)《2020年高考押题预测卷》浙江省宁波市慈溪市三山高级中学等六校2019-2020学年高二上学期期中数学试题浙江省宁波市六校联考2019-2020学年上学期高二期中数学试题江苏省苏州市陆慕高级中学2019-2020学年高二下学期在线学习质量检测数学试题人教A版(2019) 选择性必修第一册 过关斩将 第一章 空间向量与立体几何 专题强化练3 立体几何中的存在性与探究性问题(已下线)专题03 空间向量与立体几何-立体几何中的存在性与探究性问题-2021-2022学年高二数学同步练习和分类专题教案(人教A版2019选择性必修第一册)福建省建瓯市芝华中学2021-2022学年高二上学期第一次阶段性检测数学试题安徽省蚌埠市五河致远实验学校、固镇县汉兴学校2023-2024学年高二上学期10月联考数学试题
解题方法
4 . 如图,在直三棱柱
中,
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/29/a3acc036-e01d-48a6-8ef3-1a66c959410a.jpg?resizew=126)
(1)证明:
平面
;
(2)若
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36cf3bff56a7f4ab6c0008e90823025d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/289d7a880379d6060065c829b45b0ed6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/29/a3acc036-e01d-48a6-8ef3-1a66c959410a.jpg?resizew=126)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67d85c8d87197c9ffad619eb3912e1b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6610370a5aefaf45fdb579521484e3b5.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6e937690538483bca282ff6831772b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3bdeec91171e6d0c5247f199ffd7c63.png)
您最近一年使用:0次
2018-03-26更新
|
802次组卷
|
4卷引用:2017届河南豫北名校联盟高三文上精英对抗赛数学试卷2
2013高三·天津·竞赛
5 . 在正三棱柱
中,
为边
的中点.
(1)证明:
平面
.
(2)当
取何值时,
?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be0c0d0497f5d3f317504d59cc19a4c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bf9628142422a4884bd59538da6d312.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f6df10d0b03d6f6e640d9c5f3695a4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fa8345302e8036af33d4598282144d7.png)
您最近一年使用:0次
解题方法
6 . 如图,在三棱柱
中,
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/5/0165774f-225f-4557-afa7-056fea9613d2.png?resizew=169)
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d8772aa893a9c1d40f714cb25701701.png)
平面
;
(2)若
,求证
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/5/0165774f-225f-4557-afa7-056fea9613d2.png?resizew=169)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d8772aa893a9c1d40f714cb25701701.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74bca84ad86c648d3bb20c8909c8da3f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c287bb15494297df234f700f9f3a90d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fffbf41f3890efb6956907ad3c4062a0.png)
您最近一年使用:0次
解题方法
7 . 如图,在三棱柱
中,
为
的重心,
.
![](https://img.xkw.com/dksih/QBM/2016/12/24/1619404811419648/1619404811993088/STEM/a0919343-4619-4c8e-92fb-47590f964abb.png?resizew=237)
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91f3956f008cc29ca4bae44a087d5427.png)
平面
;
(2)若侧面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
底面
,
,
,求直线
与平面
所成角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ec23977096e2408f069d182cbb84952.png)
![](https://img.xkw.com/dksih/QBM/2016/12/24/1619404811419648/1619404811993088/STEM/a0919343-4619-4c8e-92fb-47590f964abb.png?resizew=237)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91f3956f008cc29ca4bae44a087d5427.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fce1ddb7003591b033b1a58dc55ede7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)若侧面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/981978eee3927889e8527272c98468b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/002c709e9fee8d477bddfe595cc760f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2d97cfada1116cc8e03d66f8e0d24cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
您最近一年使用:0次
2017-02-08更新
|
1147次组卷
|
3卷引用:2017届河南豫北名校联盟高三理上精英对抗赛数学试卷1